The paddle-type boats referenced herein are generally small, human-powered boats that are traditionally rowed over a body of water and such boats may include, but are not limited to kayaks, canoes, and rafts. By way of example, one type of paddle-type boat may take the form of a kayak with a covered deck, and one or more cockpits, each seating one paddler who strokes a double-bladed paddle. The cockpit is generally covered by a spraydeck that keeps the inside of the boat and the paddler's lower body dry. The spraydeck or similar waterproof covering attaches securely to the edges of the cockpit, preventing the entry of water from waves or spray.
An inflatable kayak, also known as a ducky, can usually be transported by hand using a carry bag. An outer skin, cover or shell of a conventional inflatable kayak may be made from hypalon (a kind of neoprene), a polyvinyl chloride fabric, or a polyurethane coated cloth. They may have a nylon covering with bladders inflatable within the covering. They can be inflated with foot, hand, or electric pumps and may include multiple air compartments for increased safety. Inflatable kayaks also typically include a top covering having a spraydeck.
For kayaks and canoes in particular, especially since they are designed to be paddled over longer distances and across large bodies of water, having a sail to propel the kayak or canoe may be advantageous and help save valuable energy that would otherwise be expended through paddling. Conventional sails for these types of vessels are typically supported with a static mounting that does not allow for quick dousing or de-powering. The ease and speed of taking down the sail is paramount to safety while sailing in a small vessel like a canoe or kayak. If an increase in wind speed or undesired change in wind direction occurs, the rigidly attached sail may be over powered and upset, which may result in a capsizing event. The rigging and mounts for some conventional sails may also add unwanted weight or rigid elements that should be avoided with an inflatable kayak.
Some conventional sails currently available for kayaks and canoes include the SPIRIT SAILS® sailrigs made by Downwind, LLC, and which takes the form of a V-shaped sail firmly connected to the boat. The sail remains up and deployed without the ability to instantly douse or take it down in the event of a sudden increase in wind speed.
The QUIVERSAIL® sail made by QuiverSail, Inc. is also a V-shaped sail with stiffening members that can be either fastened to the deck of a kayak or canoe or hand held. The ZEPHYR™ sail has a kite-like shape with no stiffeners and is hand-flown from a two-manned kayak or canoe. The PACIFIC ACTION™ sail made in New Zealand is also a V-shaped sail held with twin vertical masts in its vertical orientation with stabilizing cord.
Other conventional sails are described in U.S. Pat. No. 1,859,178 to Sprinkle; U.S. Pat. No. 4,082,049 to April; U.S. Pat. No. 5,289,792 to Forrest et al; U.S. Pat. No. 5,377,607 to Ross; U.S. Pat. No. 6,390,013 to Cornell; U.S. Pat. No. 6,457,430 to Drabkin; U.S. Pat. No. 6,615,758 to Blad; U.S. Pat. No. 6,655,314 to Housely et al; U.S. Pat. No. 6,776,115 to DeMeo; and U.S. Pat. No. 6,807,919 to Thomsen.
U.S. Patent Publication No. 2009/0139438 to Wiltz describes a sail for propelling watercraft and land vehicles. Wiltz teaches the sail is constructed with a substantially rigid, yet foldable and elastic perimeter batten that supports a flexible sail structure to capture wind energy. The flexible sail structure includes a hollow body defining a substantially hemispherical shape when fully expanded by the captured wind. A perimeter sleeve is provided at a front end of the sail structure for housing the batten. The batten is a single, closed-loop structure made of a resilient material. The sail uses the flexible properties of its batten to both support the wind-harnessing flexible sail structure as well as to compactly fold itself into a geometrical size less than its original deployment size when twisted and coiled upon itself as three contiguous coils.